Improvement in car-brakes



T. E. THOMPSON.

v CAR-BRAKE. 1\Io.'173,8?.9.` Paten-ted Feb. zz, 1876.

UNITED STATES PATENT OFFICE THOMASv E. THOMPSON, OF RICHMOND, INDIANA,ASSIGNOR OF PART INTEREST TO Gr. MORGAN ELDRIDGE, ORPHILADELPHIA, PA.

IMPRovEMEN-r IN CAR-BRAKES.

Specification -forming part of Letters Patent No. 173,829, datedFebruary 22, 1876; application tiled June 14, 1875. i

To all whom it may concern:

Be it known that I, THoMAsE. THOMPSON,

lof thecity of Richmond, in the county of backward without interferenceby the brakes.

The draw-bar of acar as at present constructy ed has a movement of someinches when two cars are thrust together, but returns to its place bythe action ot' its spring when pressure is relieved.' It is ot' thismovement that I avail myself.

The draw-bar A, Fig. 1, is` extended by a prolongation, B, to the lineof the brake-bar, or thereabout, and at its extremity it is connectedwith a lever, C, which is attached Vto the brake-bar D, and at its lowerend to a rod, E, which extends to and connects with the other brake-bar.With brakes inside the wheels the extension of the draw-bar is carriedbeyond the center of the truck, and the lever is attached to the-fartherbrakebar, and .the connecting-rod is a pressure-rod; but with brakesoutside the wheels the lever is attached to the brake-bar ot' the nearerwheels, and the connecting-rod becomes a draft-rod.

It will be readily seen that if while a train is in motion thelocomotive is restrained the car next to it 'will thrust upon it, andthat this thrust will be at once transmitted to the brake-shoes by meansofthe lever and connecting-rod, eectually braking the train andrestraining the car until it ceases to press forward; when the brakeswill be at once reare free; but it is clear that with this appliance,and without more it will be impossible to push the car back, because thethrust will come entirely upon the brakes, and will et'- fectuallyprevent the revolution of the wheels.

To obviate this I so adjust the length ofthe connecting rod that whenthe draw-bar is pressed in the brake-shoes are brought close to, but notpressing on, the wheels; and I attach an engaging and disengaging gear,by means of which the strain is put on and thrown off the brakes at theproper time, one form of the mechanism of which I shall now proceed todescribe.

Upon the axle I attach a double scroll-worm, F,which acts upon thetongue I, hereafter mentioned. The `lever U, which is shown with itsconnections in detail in Fig. 2, is jointed at the point at which itconnects with the brake-bar D, and to its lower part is attached a lug,G,

which rests upon a cam, H, by means of which the lever may bestgepgthen'ed', and the strain upon the connecting-rod tfgwhtened.Attached to this cam, and moving it, is a tongue, 1,

(shown also in' section in Fig. 3) which extends toward the axle, andlis of such length as to engage with theworm F, when the brakes arebrought close to the wheels, but to be free when the brakes are loose.,Connected with the cam, andinnnediately in therear ot it, is aneccentric, K, u'pon a rock-shaft, L,'which, being set in one position,adjusts the tongue so that it will engage with one of the Worms,

and in theother position so adjuststhe tongue.

that it will engage with the other worm. The tongue is provided with aspriu g, Mfby which it is held in its proper place ready for action. Thecar being ready to` go in a certain direction the eccentric is set inthat position which will put the tongue in placa to engagewith i theworm which runs from the center to the i circumference. .The car may nowbe backed,

because the pressure upon the draw-bar will 4 cause the brake shoes toapproach but not to press upon the wheels, and the worm near which thetongue lies does not engage with 1 it, and the car may also be drawnforward freely, but'it' While it is in mot-ion forward the locomotive isheld back `the forward thrust ofthe car is received upon the drawbar,and by means of the lever and connecting-rod the brakes are broughtclose to the wheels, and at the same time the tongue engaging with theWorm brings the cam into actionnpon the lug, straightening the lever andbringing the thrust-oi' the` car to bear upon the brakes until the caris so checked that it ceases to thrust upon the one in front of it, whenthe spring of the draw-bar presses it ont, the tongue is relieved fromthe Worm, and the brakes from the Wheels. When the car is to be drawn inthe other direction the eccentric is set the other Way, so that thetongue will engage with the other Worm.

The hand-brake may remain substantially vas it is now ordinarilyattached, Whether with the inside or outside brakes.`

Thepurpose ot'myinvention is accomplished when, by the thrust of a carin combination with mechanism impelled by the forward n10- tion ot' itsWheels, the brakes are applied and are held in action so long as thethrust continues; but are not operated by the thrust of coniine myselfto the precise form of apparatus described, for I have constructedsundry devices; and I am aware that many others can be constructed,differing in mechanicaldetail, but accomplishingthesame result.

I claim as my invention- The combination of the brake-lever directlyattached to the draw-bar and mechanism, actuated by theWheels,substantially as and for the purpose described.

THOS. E. THOMPSON.

Witnesses:

S. P. HANsoN, F. K. HIPPLE.

